Neuberger's suppressed comments came in a ruling ordering the release of information about the case of Ethiopian-born Mohamed, who was detained for nearly seven years, including over four at Guantanamo.
He claims he was "tortured in medieval ways" and alleges that MI5, the British domestic security service, colluded with his abusers.
Neuberger said evidence in the Mohamed case showed "some security services officials appear to have a dubious record relating to actual involvement, and frankness about any such involvement, with the mistreatment of Mr Mohamed when he was held at the behest of US officials".
He said he had in mind a particular unnamed witness and that "it is likely that there were others".
Neuberger added there were questions over whether statements about alleged mistreatment could be relied upon.
"Not only is there some reason for distrusting such a statement, given that it is based on security services' advice and information, because of previous, albeit general, assurances in 2005, but also the security services have an interest in the suppression of such information."